Mike Pence has long described himself as a “Christian, a conservative and a Republican in that order”.

Now, the Republican vice-presidential nominee and his priorities are facing a critical test as Donald Trump, staggered by his recorded vulgarities about women, careens towards the second presidential debate against Democrat Hillary Clinton – beginning 9am on Monday HKT.

We impeached Bill Clinton and we cannot impeach Trump off the ballot. But I wish there was a mechanism to do so

Mike Murphy, public relations strategist

“We pray for his family and look forward to the opportunity he has to show what is in his heart when he goes before the nation tomorrow night,” the Indiana governor said.

It’s more evidence of the trials facing the Republican ticket’s No. 2 that could serve Pence well if he runs for the top spot in 2020. Pence dare not speak about that possibility. To do so would assume Clinton prevails on November 8. But plenty of people are engaging in presidential talk about Pence, including Republican members of Congress, governors, a former presidential candidate, and more.

Pence cancelled his appearance at a Wisconsin rally on Saturday with House Speaker Paul Ryan. Pence would have been expected to advocate for Trump.

“I’m sure he’s horrified,” said Mike Murphy, an Indiana public relations strategist who’s known Pence for more than two decades. “We impeached Bill Clinton and we cannot impeach Trump off the ballot. But I wish there was a mechanism to do so.”

Pence raised his political stock on Monday night during the only debate against Democrat Tim Kaine. During the 90-minute event, Pence managed to not defend Trump’s indefensible behaviour, yet still sound supportive and show off his own expertise on foreign policy.

The performance highlighted the gulf in political sophistication between Trump and his running mate. Pence addressed the awkwardness with a savvy statement acknowledging his own performance and preserving his alliance with Trump.

“People are saying that I won the debate,” he said on Wednesday in Harrisonburg, Virginia. “From where I sat, Donald Trump’s vision to make America great won the debate.”

But on Friday, Trump’s behaviour put Pence to an even tougher test. The Washington Post and NBC broke the story of Trump’s words about women as Pence advocated for Trump him in Ohio.

“With Donald Trump as president, we’ll have a president of the United States who respects all the American people,” Pence said as news of Trump’s comments was breaking.

Pence went on to defend, as he has previously, Trump’s outspoken nature as a refusal to “tiptoe around those thousands of rules of political correctness”. Pence ignored shouted questions about Trump, and he was quickly whisked out of reach of the news media.

What followed: Pence’s silence, the scrapping of his Wisconsin appearance and finally, his statement.

An influential Indiana conservative, Jim Bopp, who helped draft this year’s Republican Party platform, said Pence “should stay the course”.

Trump’s words are “ill-considered and crude”, Bopp said, and also “statements Mike Pence would never make”.

The election is bigger than that, said Bopp, a lawyer from Terre Haute, Indiana.

“In the grand scheme of things, this is trivia versus real life-and-death problems that we face in our foreign policy and the serious challenges that everyday Americans face because of the Obama-Clinton economy,” Bopp said.